I also notice the bolts on the ends of the exhaust manifolds. If it was me, I'd replace them with studs and nuts or there will be lots of cursing later when you have to remove them in situ. I made the mistake of installing the manifold setup with the engine on the stand and later had to take the rear bolt out when it was in the truck. It required much quality time with a bench grinder and a Husky brand 9/16 combo wrench.
